Granule coated with urethane resin

ABSTRACT

A coated granule is obtained by coating a bioactive substance-containing granule with a urethane resin obtained by reaction of an aromatic diisocyanate with a polyol mixture containing a polyesterpolyol and a C2-C8 polymethylene glycol, wherein the molar ratio of the polyesterpolyol to the polymethylene glycol is 1:20 to 20:1. The granule is capable of controlling elution of the bioactive substance appropriately, and the urethane resin forming the coating film shows degradability in soil.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a section 371 of International Application No.PCT/JP2007/066063, filed Aug. 13, 2007, which was published in theEnglish language on Feb. 19, 2009 under International Publication No. WO2009/022431 A1 and the disclosure of which is incorporated herein byreference.

TECHNICAL FIELD

The present invention relates to a granule coated with a urethane resin.

BACKGROUND TECHNOLOGY

There is suggested a technology of coating a bioactive ingredient forfertilizers, pesticides and the like with a coat film, therebycontrolling elution appropriately, so as to cause elution thereof atgiven period according to the growth of plants.

Recently, enhanced attention is paid to easily degradable resins forthoughtful consideration for the environment. JP 11-130576A and JP7-505B disclose granules coated with polycaprolactone and polyethyleneor the like. With coated granules of fertilizers, however, it isdifficult to control elution using an easily degradable resin as a coatfilm so as to elute a fertilizer component at given period.

SUMMARY OF THE INVENTION

According to the present invention, with a coated granule of a bioactivesubstance, use of a urethane resin obtained by reacting an aromaticdiisocyanate with a polyol mixture comprising a polyesterpolyol and aC2-C8 polymethylene glycol, wherein the molar ratio of thepolyesterpolyol to the polymethylene glycol is 1:20 to 20:1.

That is, the present invention includes the following inventions.

[Invention 1]

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reaction of an aromaticdiisocyanate with a polyol mixture comprising a polyesterpolyol and aC2-C8 polymethylene glycol, wherein the molar ratio of thepolyesterpolyol to the polymethylene glycol is 1:20 to 20:1. The molarratio of the polyesterpolyol to the polymethylene glycol means a ratioof the number of the hydroxyl group of the polyesterpolyol to the numberof the hydroxyl group of the polymethylene glycol throughout thedescription.

[Invention 2]

The coated granule described in Invention 1, wherein the polyesterpolyolhas 15 wt % or more of an oxycarbonyl structure (—O—C(═O)—) part in themolecule.

[Invention 3]

The coated granule described in Invention 1 or 2, wherein the amount ofthe polyesterpolyol is 15 to 80 parts by weight based on 100 parts byweight of the total amount of the aromatic diisocyanate and the polyol.

[Invention 4]

The coated granule described in any one of Inventions 1 to 3, whereinthe polyesterpolyol is polycaprolactonepolyol.

[Invention 5]

The coated granule described in Invention 4, wherein the amount of thepolycaprolactonepolyol is 20 to 70 parts by weight based on 100 parts byweight of the total amount of the aromatic diisocyanate and the polyol.

[Invention 6]

The coated granule described in any one of Inventions 1 to 5, whereinthe amount of the polymethylene glycol is 1 to 25 parts by weight basedon 100 parts by weight of the total amount of the aromatic diisocyanateand the polyol.

[Invention 7]

The coated granule described in any one of Inventions 1 to 6, whereinthe polymethylene glycol is 1,4-butandiol or 1,6-hexanediol.

[Invention 8]

The coated granule described in any one of Inventions 1 to 7, whereinthe amount of the aromatic diisocyanate is 10 to 49 parts by weightbased on 100 parts by weight of the total amount of the aromaticdiisocyanate and the polyol.

[Invention 9]

The coated granule described in any one of Inventions 1 to 8, whereinthe aromatic diisocyanate is 4,4′-diphenylmethanediisocyanate.

[Invention 10]

The coated granule described in Invention 1, wherein the polyolcomprises polyesterdiol, C2-C8 polymethylene glycol and triol.

[Invention 11]

The coated granule described in Invention 10, wherein the amounts of thepolyesterdiol, C2-C8 polymethylene glycol, triol and aromaticdiisocyanate are 20 to 55 parts, 1 to 15 parts, 10 to 40 parts and 10 to49 parts by weight, respectively, based on 100 parts by weight of thetotal amount of the aromatic diisocyanate and the polyol.

[Invention 12]

The coated granule described in Invention 1, wherein the polyolcomprises polycaprolactonepolyol, C2-C8 polymethylene glycol and atleast one selected from the group consisting of castor oil andhydrogenated castor oil.

[Invention 13]

The coated granule described in Invention 12, wherein the amounts of thepolycaprolactonepolyol, C2-C8 polymethylene glycol, castor oil and/orhydrogenated castor oil and aromatic diisocyanate are 20 to 55 parts, 1to 15 parts, 10 to 40 parts and 10 to 49 parts by weight, respectively,based on 100 parts by weight of the total amount of the aromaticdiisocyanate and the polyol.

[Invention 14]

The coated granule described in any one of Inventions 1 to 13, whereinthe bioactive substance is a fertilizer.

[Invention 15]

The coated granule described in any one of Inventions 1 to 13, whereinthe bioactive substance is a pesticide. de

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

According to the present invention, the coated granule containing abioactive substance is coated with a resin easily degradable in soil andshows excellent elution controllability of the bioactive substance.

The urethane resin used as a film for providing the coated granularmaterial of the present invention is a urethane resin obtained byreaction of an aromatic diisocyanate with a polyol mixture comprising apolyesterpolyol and a C2-C8 polymethylene glycol. The molar ratio of thepolyesterpolyol to the polymethylene glycol is 1:20 to 20:1.

The polyesterpolyol is preferably a polyesterpolyol having 15 wt % ormore of an oxycarbonyl structure (—O—C(═O)—) part in the molecule.

The polyesterpolyol is generally polylactonepolyol, which means acompound produced by ring-opening-polymerizing a lactone monomer with alow molecular weight polyol. Examples of the lactone monomer includeβ-propiolactone, γ-butyrolactone, δ-valerolactone and ε-caprolactone.Examples of the low molecular weight polyol include divalent alcoholsuch as ethylene glycol, diethylene glycol, propylene glycol,1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol and 1,8-octanediol; andtrivalent alcohol such as2-ethyl-2-(hydroxymethyl)-1,3-propanediol(trimethylolpropane),2-(hydroxymethyl)-1,3-propanediol, glycerin and triethanolamine.

Preferable polyesterpolyol is polycaprolactonepolyol, which is acompound produced by ring-opening-polymerizing an ε-caprolactone monomerwith the above-mentioned low molecular weight polyol. Typical chemicalstructures of the polycaprolactonepolyol(polycaprolactonediol orpolycaprolactonetriol) having two or three hydroxyl groups in onemolecule are shown below. This polycaprolactonepolyol is a polyol havingat least one (1-oxohexa-1,6-diyl)oxy structure(—C(═O)—CH₂—CH₂—CH₂—CH₂—CH₂—O—) in one molecule.

[wherein, m represents an integer of 0 or more, n represents an integerof 1 or more and m+n is 2 or more, and R¹ represents a divalent organicgroup (for example, ethylene group, tetramethylene group and the like)].

[wherein, m and p represent an integer of 0 or more, n represents aninteger of 1 or more and m+n+p is 2 or more, and R² represents atrivalent organic group (for example, propane-1,2,3-triyl group and thelike)].

For example, a polycaprolactonepolyol produced byring-opening-polymerizing 6 moles of ε-caprolactone with one mole ofethylene glycol has the following formula:HO—[CH₂—CH₂—CH₂—CH₂—CH₂—C(═O)—O]₃—CH₂—CH₂—[O—C(═O)—CH₂—CH₂—CH₂—CH₂—CH₂]₃—OH

The polycaprolactonepolyol has about 35 wt % of an oxycarbonyl structure(—O—C(═O)—) part in the molecule, namely,(44×6)/(62+114×6)=0.354wherein, each molecular weight of ε-caprolactone and ethylene glycol is114 and 62, respectively, and the oxycarbonyl structure has 44 of themolecular weight.

Further, the equivalent weight of the hydroxyl group to thepolycaprolactonepolyol is 373, namely,(62+114×6)/2=373wherein, the molecular weight of the ε-caprolactone is divided by thenumber of the hydroxyl group.

The molecular weight of the polycaprolactonepolyol is preferably 300 to5000, more preferably 400 to 2500. Further, the equivalent weight of thehydroxyl group to the polycaprolactonepolyol is usually 200 to 1250.

The amount of the polyesterpolyol is usually 15 to 80 parts by weight,preferably 20 to 70 parts by weight, based on 100 parts by weight of thetotal amount of the aromatic diisocyanate and the polyol.

Examples of the C2-C8 polymethylene glycol include ethylene glycol,1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol and1,8-octanediol. Among them, 1,4-butanediol and 1,6-hexanediol arepreferable. The amount of the polymethylene glycol is usually 1 to 25parts by weight based on 100 parts by weight of the total amount of thearomatic diisocyanate and the polyol.

Examples of the aromatic diisocyanate include diisocyanate compoundshaving one or two benzene rings such as 4,4′-diphenylmethanediisocyanate (MDI), tolylene diisocyanate (TDI), xylylene diisocyanate(XDI), tolidine diisocyanate (TODI) and tetramethylenexylylenediisocyanate (TMXDI); and diisocyanate compounds having a naphthalenering such as naphthalene 1,5-diisocyanate (NDI). Prepolymer such as areaction product of the above-mentioned aromatic diisocyanate with apolyol may be used as the aromatic diisocyanate. Among them, MDI ispreferable. The amount of the aromatic diisocyanate is usually 10 to 49parts by weight based on 100 parts by weight of the total amount of thearomatic diisocyanate and the polyol.

In an embodiment of the present invention, the polyol mixture forproviding the urethane resin comprises a polyesterdiol (e.g.,polycaprolactonediol), a C2-C8 polymethylene glycol and a triol (e.g.,polycaprolactonetriol, castor oil, hydrogenated castor oil). The amountsof the polyesterdiol, C2-C8 polymethylene glycol, triol and aromaticdiisocyanate are usually 20 to 55 parts, 1 to 15 parts, 10 to 40 partsand 10 to 49 parts by weight, respectively.

In an embodiment of the present invention, the polyol mixture forproviding the urethane resin comprises a polycaprolactonepolyol and aC2-C8 polymethylene glycol, and at least one selected from the groupconsisting of castor oil and hydrogenated (hardened) castor oil. Theamounts of the polycaprolactonepolyol, C2-C8 polymethylene glycol,castor oil and/or hydrogenated castor oil and aromatic diisocyanate areusually 20 to 55 parts, 1 to 15 parts, 10 to 40 parts and 10 to 49 partsby weight, respectively.

In the present invention, the molar ratio of the isocyanate (NCO) groupin the aromatic diisocyanate to the hydroxyl (OH) group in the polyolmixture is generally 1:0.9-1:1.5, preferably 1:1-1:1.2.

The urethane resin is produced usually by reacting an aromaticdiisocyanate and a polyol, if necessary in the presence of a catalyst,on the surface of a bioactive substance-containing granule or on a coatfilm covering a bioactive substance-containing granule.

The reaction of an aromatic diisocyanate and a polyol is notparticularly restricted, and can be carried out by, for example, amethod in which all aromatic diisocyanates and polyols are mixed andhardened, a method in which an aromatic diisocyanates and a part ofpolyols are mixed previously to prepare a polyisocyanate-terminalprepolymer, then, remaining polyols are mixed and hardened, and other,methods. Further, it is also possible that a small amount of organicsolvent is mixed with a diisocyanate and a polyol, and a solvent isremoved simultaneously with the reaction. The reaction conditionsthereof can be selected arbitrarily, however, when the temperature israised, the reaction speed of a hydroxyl group and an isocyanate groupincreases. By adding a catalyst, the reaction speed can be accelerated.

Examples of the catalyst to be used for production of a urethane resininclude organometal compounds such as potassium acetate, calciumacetate, stannous octoate, dibutyltin diacetate, dibutyltin dichloride,dibutyltin dilaurate, dibutinthiostannic acid, stannous octylate,di-n-octyltin dilaurate, isopropyl titanate, bismuth 2-ethyl hexanoate,phosphine, zinc neodecanoate, tetrabutyl titanate, oxyisopropylvanadate, n-propyl zirconate and the like, and amine catalysts such astriethylamine, N,N,N′,N′-tetramethylethylenediamine, triethylenediamine,N-methylmorpholine, N,N-dimethyldidodecylamine, N-dodecylmorpholine,N,N-dimethylcyclohexylamine, N-ethylmorpholine, dimethylethanolamine,N,N-dimethylbenzylamine, 2,4,6-tris(dimethylaminomethyl)phenol and thelike.

A mixture having flowability of an aromatic diisocyanate and a polyol(further, catalyst to be added if necessary), before sufficient reactionof a diisocyanate group in the aromatic diisocyanate and a hydroxylgroup in the polyol, is expressed as an unhardened urethane resin insome cases.

The coated granule of the present invention is a coated granule obtainedby coating a bioactive substance-containing granule with a urethaneresin, and the coat using a urethane resin suppresses elution of abioactive substance in the bioactive substance-containing granule. Inthe present invention, mentioned as the bioactive substance contained inthe bioactive substance-containing granule are insecticides, fungicides,herbicides, plant growth regulating agents, repellents, fertilizers andthe like.

Examples of the pesticidal ingredient for insecticides, fungicides,herbicides, plant growth regulating agents, repellents and the likeinclude organophosphorus compounds such as fenitrothion [O,O-dimethylO-(3-methyl-4-nitrophenyl)phosphorothioate], fenthion[O,O-dimethylO-(3-methyl-4-(methylyhio)phenyl)phosphorothioate], diazinon[O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate],chlorpyrifos[O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate],acephate[O,S-dimethyl acetylphosphoramidothioate], methidathion [S-2,3-dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-ylmethyl O,O-dimethylphosphorodithioate], disulfoton[O,O-diethyl S-2-ethylthioethylphosphorodithioate], DDVP[2,2-dichlorovinyl dimethylphosphate],sulprofos[O-ethyl O-4-(methylyhio)phenyl S-propylphosphorodithioate],cyanophos[O-4-cyanophenyl O-dimethyl phosphorothioate], dioxabenzofos[2-methoxy-4H -1,3,2-benzodioxaphosphorine-2-sulfide], dimethoate[O,O-dimethyl S-(N-methylcarbamoylmethyl)dithiophosphate], phenthoate[ethyl 2-dimethoxyphosphinothioyl(phenyl)acetate], malathion[diethyl(dimethoxyphosphinothioylthio)succinate], trichlorfon[dimethyl2,2,2-trichloro-1-hydroxyethylphosphonate],azinphos-methyl[S-3,4-dihydro-4-oxo-1,2,3-benzotriazin-3-ylmethylO,O-dimethyl phosphorodithioate], monocrotophos[dimethyl(E)-1-methyl-2-(methylcarbamoyl)vinyl phosphate] and ethion[O,O,O′,O′-tetraethyl S,S′-methylenebis (phosphorodithioate)]; carbamatecompounds such as BPMC[2-sec-butylphenyl methylcarbamate],benfuracarb[ethylN-{2,3-dihydro-2,2-dimethylbenzofuran-7-yloxycarbonyl(methyl)aminothio}-N-isopropyl-β-alaninate],propoxur[2-isopropoxyphenyl N-methylcarbamate],carbosulfan[2,3-dihydro-2,2-dimethyl-7-benzo[b]furanylN-dibutylaminothio-N-methylcarbamate], carbaryl[1-naphthylN-methylcarbamate],methomyl[S-methyl-N-(methylcarbamoyloxy)thioacetimidate],ethiofencarb[2-(ethylthiomethyl)phenyl methylcarbamate],aldicarb[2-methyl-2-(methylthio)propionaldehyde O-methylcarbamoyloxime],oxamyl[N,N-dimethyl-2-methylcarbamoyloxyimino-2-(methylthio)acetamide]and fenothiocarb[S-4-phenoxybutyl N,N-dimethylthiocarbamate]; pyrethroidcompounds such asetofenprox[2-(4-ethoxyphenyl)-2-methyl-1-(3-phenoxybenzyl)oxypropane],fenvalerate[(RS)-α-cyano-(3-phenoxybenzyl)(RS)-2-(4-chlorophenyl)-3-methylbutyrate],esfenvalerate[(S)-α-cyano-(3-phenoxybenzyl)(S)-2-(4-chlorophenyl)-3-methylbutyrate],fenpropathrin[(RS)-α-cyano-(3-phenoxybenzyl)2,2,3,3-tetramethylcyclopropanecarboxylate],cypermethrin[(RS)-α-cyano-(3-phenoxybenzyl)(1RS)-cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate],permethrin[3-phenoxybenzyl(1RS)-cis,trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate],cyhalothrin [(RS)-α-cyano-(3-phenoxybenzyl)(1RS,3Z)-cis-3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylate],deltamethrin[(S)-α-cyano-3--phenoxybenzyl(1R)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate],cycloprothrin[(RS)-α-cyano-3-phenoxybenzyl(RS)-2,2-dichlorovinyl-1-(4-ethoxyphenyl) cyclopropanecarboxylate],fluvalinate [α-cyano-3-phenoxybenzylN-(2-chloro-α,α,α-trifluoro-p-tolyl)-D-valinate], biphenthrin[2-methyl-3--phenylbenzyl(1RS,3Z)-cis-3-(2-chloro-3,3,3-trifluoro-1-propenyl)-2,2-dimethylcyclopropanecarboxylate],halfenprox[2-(4-bromodifluoromethoxyphenyl)-2-methyl-1-(3-phenoxybenzyl)methylpropane], tralomethrin [(S)-α-cyano-3--phenoxybenzyl(1R)-cis-3-(1,2,2,2-tetrabromoethyl)-2,2--dimethylcyclopropanecarboxylate],silafluofen[(4-ethoxyphenyl)-{3-(4-fluoro-3-phenoxyphenyl)propyl}dimethylsilane],d-phenothrin [3--phenoxybenzyl(1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate], cyphenothrin [(RS)-α-cyano-3-phenoxybenzyl(1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate], d-resmethrin [5-benzyl-3--furylmethyl(1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate],acrinathrin [(S)-α-cyano-3-phenoxybenzyl(1R,3Z)-cis-2,2-dimethyl-3-{3-oxo-(1,1,1,3,3,3-hexafluoropropyloxy)propenyl}cyclopropanecarboxylate],cyfluthrin [(RS)-α-cyano-4-fluoro-3-phenoxybenzyl3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate], tefluthrin[2,3,5,6-tetrafluoro-4-methylbenzyl(1RS,3Z)-cis-3-(2-chloro-3,3,3-trifluoro-1-propenyl)-2,2-dimethylcyclopropanecarboxylate],transfluthrin [2,3,5,6-tetrafluorobenzyl(1R)-trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate],tetramethrin [3,4,5,6-tetrahydrophthalimidomethyl(1RS)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate],allethrin[(RS)-2-methyl-4-oxo-3-(2-propenyl)-2-cyclopenten-1-yl(1RS)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate],prallethrin[(S)-2-methyl-4-oxo-3-(2-propynyl)-2-cyclopenten-1-yl(1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate],empenthrin[(RS)-1-ethynyl-2-methyl-2-pentenyl(1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate],imiprothrin [2,5-dioxo-3-(2-propynyl)imidazolidin-1-ylmethyl(1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylate],d-furamethrin [5-(2-propynyl)furfuryl (1R)-cis,trans-2,2-dimethyl-3-(2-methyl-1-propenyl) cyclopropanecarboxylate] and5-(2-propynyl)furfuryl 2,2,3,3-tetramethylcyclopropanecarboxylate;thiadiazine derivatives such as buprofezin[2-tert-butylimino-3-isopropyl-5-phenyl-1,3,5-thiadiazin-4-one];nitroimidazolidine derivatives; nereistoxin derivatives such as cartap[S,S′-(2-dimethylaminotrimethyl)bis(thiocarbamate)], thiocyclam[N,N-dimethyl-1,2,3-trithian-5-ylamine] and bensultap[S,S′-2-dimethylaminotrimethylenedi (benzenethiosulfonate);N-cyanoamidine derivatives such asN-cyano-N′-methyl-N′-(6-chloro-3-pyridylmethyl) acetamidine; chlorinatedhydrocarbon compounds such as endosulfan[6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepineoxide], γ-BHC[1,2,3,4,5,6-hexachlorocyclohexane] and dicofol[1,1-bis(4-chlorophenyl)-2,2,2-trichloroethanol]; benzoylphenylureacompounds such as chlorfluazuron[1-{3,5-dichloro-4-(3-chloro-5-trifluoromethylpyridin-2-yloxy)phenyl}-3-(2,6-difluorobenzoyl)urea], teflubenzuron[1-(3,5-dichloro-2,4-difluorophenyl)-3-(2,6-difluorobenzoyl) urea] andflufenoxuron[1-{4-(2-chloro-4-trifluoromethylphenoxy)-2-fluorophenyl}-3-(2,6-difluorobenzoyl)urea];formamidine derivatives such as amitraz[N,N-{(methylimino)dimethylidine}-di-2,4-xylidine] and chlorodimeform[N′-(4-chloro -2-methylphenyl)-N,N-dimethylmethinimidamide]; thioureaderivatives such asdiafenthiuron[N-(2,6-diisopropyl-4-phenoxyphenyl)-N′-t-butylcarbodiimide];N-phenylpyrazole compounds; metoxadiazon[5-methoxy-3-(2-methoxyphenyl)-1,3,4-oxadiazol-2(3H)-one];bromopropylate [isopropyl 4,4′-dibromobenzilate]; tetradifon[4-chlorophenyl 2,4,5-trichlorophenyl sulfone]; chinomethionat [S,S-6-methylquinoxaline-2,3-diyldithiocarbonate]; propargite[2-(4-tert-butylphenoxy)cyclohexylprop-2-yl sulfite]; fenbutatin oxide[bis{tris(2-methyl-2-phenylpropyl)tin}oxide]; hexythiazox[(4RS,5RS)-5-(4-chlorophenyl)-N-chlorohexyl-4-methyl-2-oxo-1,3-thiazolidine-3-carboxamide];clofentezine [3,6-bis(2-chlorophenyl)-1,2,4,5-tetrazine]; pyridaben[2-tert-butyl-5-(4-tert-butylbenzylthio)-4-chloropyridazin-3(2H)-one];fenpyroximate [tert-butyl (E)-4-[(1,3-dimethyl-5-phenoxypyrazol-4-yl)methyleneaminooxymethyl]benzoate]; tebufenpyrad[N-4-tert-butylbenzyl]-4-chloro-3-ethyl-1-methyl-5-pyrazolcarboxamidel;polynactin complex [tetranactin, dinactin, trinactin]; pyrimidifen[5-chloro-N-[2-{4-(2-ethoxyethyl)-2,3-dimethylphenoxy}ethyl]-6-ethylpyrimidine-4-amine];milbemectin; abamectin, ivermectin; azadirachtin [AZAD]; 5-methyl[1,2,4]triazolo[3,4-b]benzothiazol; methyl1-(butylcarbaraoyl)benzimidazol-2-carbamate;6-(3,5-dichloro-4-methylphenyl)-3(2H)-pyridazinone;1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butanone;(E)-4-chloro-2-(trifluoromethyl)-N-[1-(imidazol-1-yl)-2-propoxyethylidene]aniline;1-[N-propyl-N-[2-(2,4,6-trichlorophenoxy)ethyl]carbamoyl]imidazole;(E)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)-1-penten-3-ol;1-(4-chlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pentan-3-ol;(E)-1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)penten-3-ol;1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pentan-3-ol;4-[3-(4-tert-butylphenyl)-2-methylpropyl]-2,6-dimethylmorpholine;2-(2,4-dichlorophenyl)-1-(1H-1,2,4-triazol-1-yl)hexan-2-ol; O,O-diethylO-2-quinoxalinyl phosphorothioate; O-(6-ethoxy-2-ethyl-4-pyromidinyl)O,O-dimethyl phosphorothioate; 2-diethylamino-5,6-dimethylpyrimidin-4-yldimethylcarbamate; 4-(2,4-dichlorobenzoyl)-1,3-dimethyl-5-pyrazolylp-toluenesulfonate;4-amino-6-(1,1-dimethylethyl)-3-methylthio-1,2,4-triazin-5(4H)-one,2-chloro-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) aminocarbonyl]benzenesulfonamide;2-methoxycarbonyl-N-[(4,6-dimethoxypyrimidin-2-yl)aminocarbonyl]benzenesulfonamide;2-methoxycarbonyl-N-[(4,6-dimethylpyrimidin-2-yl)aminocarbonyl]benzenesulfonamide;2-methoxycarbonyl-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)aminocarbonyl]benzenesulfonamide;2-ethoxycarbonyl-N-[(4-chloro-6-methoxypyrimidin-2-yl)aminocarbonyl]benzenesulfonamide;2-(2-chloroethoxy)-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)aminocarbonyl]benzenesulfonamide;2-methoxycarbonyl-N-[(4,6-dimethoxypyrimidin-2-yl)aminocarbonyl]phenylmethanesulfonamide;2-methoxycarbonyl-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)aminocarbonyl]thiophene-3-sulfonamide;4-ethoxycarbonyl-N-[(4,6-dimethoxypyrimidin-2-yl)aminocarbonyl]-1-methylpyrazole-5-sulfonamide;2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinolinecarboxylicacid;2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3-pyridinecarboxylicacid; methyl 6-(4-isopropyl-4-methyl-5-oxoimidazolin-2-yl)-m-toluate;methyl 2-(4-isopropyl-4-methyl-5-oxoimidazolin-2-yl)-p-toluate;2-(4-isopropyl-4-methyl-5-oxoimidazolin-2-yl) nicotinic acid;N-(4-chlorophenyl)methyl-N-cyclopentyl-N′-phenylurea;(RS)-2-cyano-N-[(R)-1-(2,4-dichlorophenyl)ethyl]-3,3-dimethylbutyramide;N-(1,3-dihydro-1,1,3-trimethylisobenzofuran-4-yl)-5-chloro-1,3-dimethylpyrazole-4-carboxamide;N-[2,6-dibrobo-4-(trifluoromethoxy)phenyl]-2-methyl-4-(trifluoromethyl)-5-thiazolecarboxamide;2,2-dichloro-N-[1-(4-chlorophenyl)ethyl]-3-methylcyclopropanecarboxamide;methyl(E)-2-2-6-(2-cyanophenoxy)pyrimidin-4-yloxy-phenyl-3-methoxyacrylate;5-methyl-1,2,4-triazolo[3,4-b]benzothiazole;3-allyloxy-1,2-benzisothiazole-1,1-dioxide; diisopropyl1,3-dithiolan-2-ylidenemalonate and O,O-dipropyl O-4-methylthiophosphate.

The fertilizer in the present invention is a component containingvarious elements such as nitrogen, phosphorus, potassium, silicon,magnesium, calcium, manganese, boron, iron and the like to be applied tosoil for imparting nutrients in plant cultivation, and examples thereofinclude nitrogen fertilizer components such as urea, ammonium nitrate,magnesium ammonium nitrate, ammonium chloride, ammonium sulfate,ammonium phosphate, sodium nitrate, calcium nitrate, potassium nitrate,lime nitrogen, formaldehyde-condensed urea (UF), acetaldehyde-condensedurea (CDU), isobutylaldehyde-condensed urea (IBDU) and guanyl urea (GU);phosphoric acid fertilizer components such as calcium superphosphate,triple superphosphate of lime, fused phosphorus, humus phosphorus,calcined phosphorus, sintered phosphorus, magnesiun superphosphate,ammonium polyphosphate, potassium metaphosphate, calcium metaphosphate,magnesium phosphate, ammonium sulfate phosphate, ammonium potassiumphosphate nitrate, ammonium hydrochloride phosphate and the like;potassium fertilizer components such as potassium chloride, potassiumsulfate, potassium sodium sulfate, potassium magnesia sulfate, potassiumbicarbonate, potassium phosphate and the like; silic acid fertilizercomponents such as calcium silicate and the like; magnesia fertilizercomponents such as magnesium sulfate, magnesium chloride and the like;calcium fertilized components such as calcium oxide, calcium hydroxide,calcium carbonate and the like; manganese fertilizer components such asmanganese sulfate, magnesia manganese sulfate, slag manganese and thelike; boron fertilizer components such as boric acid, borate and thelike; iron-containing fertilizer components such as steel slag and thelike.

The bioactive substance-containing granule in the present invention maybe a bioactive substance itself, or a material supporting a bioactivesubstance on a carrier. The bioactive substance-containing granule maycontain various kinds of bioactive substances. The coated granule of thepresent invention may contain several bioactive substance-containinggranules as an inner core simultaneously.

Examples of the carrier supporting a bioactive substance include kaolinminerals such as kaolinite and the like; mineral carriers such asmontmorillonite, smectite, talc, agalmatolite, hydrous calcium silicate,calcium carbonate, zeolite, terra alba and the like; plant carriers suchas cellulose, husk, starch, soybean powder and the like; water-solublecarries such as lactose, sucrose, dextrin, sodium chloride, sodiumtripolyphosphate, and the like, and these carries can be usedappropriately in combination.

In the present invention, mentioned as the bioactivesubstance-containing granule are pesticidal granules containingpesticidal active compounds such as insecticides, fungicides,herbicides, plant growth regulating agents, repellents and the like;granular fertilizers; pesticide-containing granular fertilizerscontaining fertilizers and pesticidal active ingredients, and the like.

As the coated granule of the present invention, the followingembodiments are exemplified.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting 10 to 49 parts byweight of an aromatic diisocyanate with a polyol containing 15 to 80parts by weight of a polyesterpolyol and 1 to 25 parts by weight of aC2-C8 polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting 10 to 49 parts byweight of MDI with a polyol containing 15 to 80 parts by weight of apolyesterpolyol and 1 to 25 parts by weight of a C2-C8 polymethyleneglycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting 10 to 49 parts byweight of an aromatic diisocyanate with a polyol containing 15 to 80parts by weight of polycaprolactonepolyol and 1 to 25 parts by weight ofa C2-C8 polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting 10 to 49 parts byweight of MDI with a polyol containing 15 to 80 parts by weight ofpolycaprolactonepolyol and 1 to 25 parts by weight of a C2-C8polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting 10 to 49 parts byweight of an aromatic diisocyanate consisting essentially of MDI with apolyol containing 15 to 80 parts by weight of polycaprolactonepolyolhaving 300-5000 of a molecular weight and 1 to 25 parts by weight of aC2-C8 polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonediol having 300-5000 of a molecular weightand a C2-C8 polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonediol having 300-5000 of a molecular weight,polycaprolactonetriol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonetriol having 300-5000 of a molecular weightand a C2-C8 polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonediol having 300-5000 of a molecular weight,polyoxypropylenetriol and a C2-C8 polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonediol having 300-5000 of a molecular weight,castor oil and a C2-C8 polymethylene glycol.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonediol having 300-5000 of a molecular weight,polycaprolactonetriol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol, wherein the crosslinking density is within a rangebetween 0.02 and 0.07.

The crosslinking density can be defined as below.Crosslinking density=(wt % of the triol in the polyol having 300-5000 ofa molecular weight)/(number average molecular weight of the triol)When the polyol contains two or more triols, the crosslinking density isa sum of each crosslinking density.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonetriol having 300-5000 of a molecular weightand a C2-C8 polymethylene glycol, wherein the crosslinking density iswithin a range between 0.02 and 0.07.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonediol having 300-5000 of a molecular weight,polyoxypropylenetriol and a C2-C8 polymethylene glycol, wherein thecrosslinking density is within a range between 0.02 and 0.07.

A coated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reacting MDI with a polyolmixture of polycaprolactonediol having 300-5000 of a molecular weight,castor oil and a C2-C8 polymethylene glycol, wherein the crosslinkingdensity is within a range between 0.02 and 0.07.

A coated fertilizer granule obtained by coating a fertilizer granulewith a urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol.

A coated fertilizer granule obtained by coating a fertilizer granulewith a urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight,polycaprolactonetriol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol.

A coated fertilizer granule obtained by coating a fertilizer granulewith a urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonetriol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol.

A coated fertilizer granule obtained by coating a fertilizer granulewith a urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight,polyoxypropylenetriol and a C2-C8 polymethylene glycol.

A coated fertilizer granule obtained by coating a fertilizer granulewith a urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight, castor oiland a C2-C8 polymethylene glycol.

A coated pesticide granule obtained by coating a pesticide granule witha urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol.

A coated pesticide granule obtained by coating a pesticide granule witha urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight,polycaprolactonetriol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol.

A coated pesticide granule obtained by coating a pesticide granule witha urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonetriol having 300-5000 of a molecular weight and a C2-C8polymethylene glycol.

A coated pesticide granule obtained by coating a pesticide granule witha urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight,polyoxypropylenetriol and a C2-C8 polymethylene glycol.

A coated pesticide granule obtained by coating a pesticide granule witha urethane resin obtained by reacting MDI with a polyol mixture ofpolycaprolactonediol having 300-5000 of a molecular weight, castor oiland a C2-C8 polymethylene glycol.

The coated granule of the present invention can be produced by forming acoat made of the above-mentioned urethane resin around a bioactivesubstance-containing granule, and the coating method is not particularlyrestricted. There are mentioned, for example, (1) a method in which asolution or emulsion of a urethane resin prepared separately is sprayedaround a bioactive substance-containing granule, then, a solvent isremoved to attain coating; (2) a method in which an aromaticdiisocyanate and a polyol are added simultaneously to a bioactivesubstance-containing granule, and on the surface of the bioactivesubstance-containing granule, a urethane resin is prepared to attaincoating; (3) a method in which an aromatic diisocyanate and a polyol areadded sequentially to a bioactive substance-containing granule, and onthe surface of the bioactive substance-containing granule, a urethaneresin is prepared to attain coating; and other methods.

An embodiment in the method (2) is a procedure of preparing a mixture ofall the polyols and optionally a catalyst, mixing it with the aromaticdiisocyanate just before adding to the bioactive substance-containinggranule, and then adding the resulting mixture to the bioactivesubstance-containing granule under fluidizing or tumbling condition.

Examples of the embodiments in the method (3) include a procedure ofpreparing a mixture of all the polyols in advance, adding the mixtureand the aromatic diisocyanate by turns to the bioactivesubstance-containing granule under fluidizing or tumbling condition; aprocedure of adding the aromatic diisocyanate, polyesterpolyol and C2-C8polymethylene glycol, subsequently, to the bioactivesubstance-containing granule under fluidizing or tumbling condition; anda procedure of adding the polyesterpolyol, aromatic diisocyanate andC2-C8 polymethylene glycol, subsequently, to the bioactivesubstance-containing granule under fluidizing or tumbling condition.

The reaction temperature of the aromatic diisocyanate with polyol isusually 20 to 200° C., preferably 50 to 150° C.

Desired elution suppressing ability can be obtained even if the useamount of a resin used for coating is smaller providing a coat film inthe coated granule of the present invention is uniform. Thus, it ispreferable that the urethane resin is produced by reacting the aromaticdiisocyanate and the polyol under the condition without solvent on thesurface of a granular material containing a bioactive substance.

Examples of the coated granule of the present invention used forapplications in the agricultural field include coated granularfertilizers, coated pesticidal granules, solid pesticidal microcapsules,solid pesticidal microspheres and the like.

In obtaining the coated granule of the present invention, coating can beperformed without using a solvent in resin molding, if an unhardenedurethane resin has suitable flowability for a suitable period attemperatures in producing a urethane resin.

In the coated granule of the present invention, it is preferable that aurethane resin has a hydrophobic liquid compound having a boiling pointof 100° C. or higher from the standpoint of bioactive substance elutionsuppressing ability. The hydrophobic liquid compound is usually immersedin a urethane resin or supported on its surface. The hydrophobic liquidcompound is liquid at 20° C., and examples thereof include aliphatichydrocarbons such as liquid paraffin, aromatic hydrocarbons such asphenylxylylethane, distyrylxylene, alkylbenzene (Solvesso 150; tradename of Exxon-Mobile Chemical), fatty acid ester compounds such asvegetable oils (e.g., soybean oil, cottonseed oil).

In the coated granule of the present invention, it is preferable thatthe above-mentioned hydrophobic liquid compound is contained in anamount of 0.1 to 5 wt % in the coated granular material of the presentinvention, and in general, it is preferable that the hydrophobic liquidcompound is added in an amount to an extent of slight presence of thehydrophobic liquid compound on the surface of the core granule.

The method for producing a coated granule of the present invention willbe illustrated in more detail referring to a method for producing acoated granular fertilizer as an example.

Particles of a granular fertilizer are made into fluidizing condition ortumbling condition in an apparatus such as a jet flow apparatus, rollingpan, rolling drum and the like. The size of the particle is notparticularly restricted, and usually 0.1 to 15mm, and its shape ispreferably sphere, and may also be other configuration such as cylinderand the like. The particles under fluidizing or tumbling condition are,if necessary, heated. Next, an unhardened urethane resin as a mixture ofan aromatic diisocyanate, a polyol and, a catalyst to be added ifnecessary, is added to the particle under fluidizing or tumblingcondition. The addition method may be either a method of mixingcomponents before quick addition, or a method of adding componentsseparately. Thereafter, while maintaining the fluidizing or tumblingcondition of the particles, the reaction of an isocyanate group in thearomatic diisocyanate and a hydroxyl group in the polyol is progressed,thereby, the surface of the particle is coated with a urethane resin. Itis preferable to control the amount of the urethane resin to be added sothat the thickness of a coat film formed in this one operation isusually 1 to 100 μm. Further, when larger thickness of a coat film isnecessary, the thickness of a urethane resin coat film can be increasedby repeating the above-mentioned operation.

In the coated granule of the present invention, the thickness of anurethane resin coat film is usually 1 to 600 μm, preferably 8 to 400 μm,and the amount thereof is usually 1 to 20 wt % (based on coated granularmaterial of the present invention), preferably 2 to 16 wt %.

The particle size of the coated granule of the present invention isusually in the range of 0.1 to 15 mm.

When a urethane resin has a hydrophobic liquid compound, the coatedgranular fertilizer of the present invention can be produced by a methodin which a hydrophobic liquid compound is added to the granularfertilizer simultaneously with an unhardened urethane resin, a method inwhich a hydrophobic liquid compound is added to the granular fertilizerbefore coating with a urethane resin, a method in which a hydrophobicliquid compound is added, after coating with a urethane resin, to thegranular fertilizer coated with a urethane resin, and the like, in theabove-mentioned method for producing a coated granular fertilizer, andpreferably, produced by a method in which a hydrophobic liquid compoundis added to the granular fertilizer before coating with a urethaneresin.

EXAMPLES

The present invention will be illustrated in more detailed by productionexamples and test examples mentioned later, but the present invention isnot limited to only examples.

Reference Example 1 (Production of Urethane Resin Film)

A urethane resin film was produced under the following conditions.

Polyols described in Tables 1 and 2 were melted at 50° C. and mixeduniformly with 2,4,6-tris(dimethylaminomethyl)phenol(catalyst), andthen, an aromatic diisocyanate (melted at 50° C.) was added, mixedquickly and drawn into a sheet using an applicator set at a thickness ofabout 125 μm. The drawn resin was allowed to stand at 70° C. for 3 hoursto cause hardening, obtaining urethane resin films (A) to (F) and films(a) and (b) for references.

TABLE 1 Name of Compound A B C Ref. b Diisocyanate MDI (NCO equivalent:125) 36.7 41.1 39.8 41.1 Polyol Ethylene glycol (OH equivalent: 31) 5.51,4-Butanediol (OH equivalent: 45) 10.4 1,6-Hexanediol (OH equivalent:59) 13.2 Trimethylolpropane (OH equivalent: 10.3 44.7)Polycaprolactonediol A (OH equivalent: 57.8 48.5 47.0 48.6 492) Catalyst2,4,6-Tris(dimethylaminomethyl)phenol 0.05 0.05 0.05 0.05 Total Amount(wt %) 100.05 100.05 100.05 100.05

TABLE 2 Name of Compound D E F Ref. a Diisocyanate MDI (NCO equivalent:125) 46.0 33.5 28.4 Polymethylenepolyphenylene polyisocyanate 30.1 (NCOequivalent: 136) Polyol 1,4-Butanediol (OH equivalent: 45) 11.6 4.8 2.02.0 Polycaprolactonediol B (OH 23.0 33.5 37.8 36.8 equivalent: 416)Castor oil (OH equivalent: 351) 19.4 28.2 31.9 31.1 Catalyst2,4,6-Tris(dimethylaminomethyl)phenol 0.05 0.05 0.05 0.05 Total Amount(wt %) 100.05 100.05 100.05 100.05 Crosslinking density 0.04 0.04 0.04In Tables 1 and 2 described above, MDI (Sumidur 44S, manufactured bySumika Beyer Urethane K.K.), polymethylenepolyphenylene polyisocyanate(Sumidur 44V-10, manufactured by Sumika Beyer Urethane K.K.), ethyleneglycol (manufactured by Wako Pure Chemical Industries, Ltd.),1,4-butanediol (manufactured by Wako Pure Chemical Industries, Ltd.),1,6-hexanediol (manufactured by Wako Pure Chemical Industries, Ltd.),polycaprolactonediol A (Placcel 210, manufactured by Daicel ChemicalIndustries, Ltd.), polycaprolactonediol B (Placcel 208, manufactured byDaicel Chemical Industries, Ltd.), castor oil (Castor Oil No. 1 forindustrial use, manufactured by Hokoku Corporation) and2,4,6-tris(dimethylaminomethyl)phenol (TAP, manufactured by Kayaku AkzoCorporation) were used.

Test Example 1 (Degradation of Urethane Resin Film in Soil)

Films (A), (B), (D), (E), (F), (a) and (b) were cut into a size of 20mm×20 mm and buried in soil obtained from the field in Hyogo prefecture(clay loam having a moisture content of 25.9%) and preserved at 28° C.During preservation, moisture was refilled appropriately in the soil andkept constant. Three months after, the films were recovered, washed withwater, and dried, then, reduction rate in weight of the film wasmeasured. The results are given in Table 3.

TABLE 3 Film Reduction in soil after 3 months (%) A 4.2 B 3.4 D 4.8 E4.0 F 19.6 a 2.1 b 0.6

Production Example 1

Under conditions described later, coated granular fertilizers wereproduced by coating granular urea (large granular urea, particle size:about 3 mm, number of granule per gram: 60) with urethane resins of rawmaterial compositions (A)-(D), (F) and (a) described in Tables 1 and 2.

In a rotary vessel, 1000 parts by weight of granular urea was made intotumbling condition, and the granular urea was heated up to about 70° C.by hot air. Next, 15 parts by weight of liquid paraffin was added andtumbling thereof was continued for 10 minutes. Further, 5 parts byweight of an unhardened urethane resin having the composition describedin Tables 1 and 2 was added and kept the tumbling condition underheating for 3 minutes or more. Further, addition of the unhardenedurethane resin and keeping of the tumbling condition under heating wererepeated until the total amount of the unhardened urethane resin addedreached 100 parts by weight. Thereafter, the mixture was cooled down toaround room temperature, to obtain coated granular ureas (A)-(D), (F)and (a). The unhardened urethane resin was obtained by mixing a polyoldescribed in Tables 1 and 2 (melted at 50° C.) and2,4,6-tris(dimethylaminomethyl)phenol (catalyst) uniformly, then, addingan aromatic diisocyanate (melted at 50° C.) directly before addition,and mixing them quickly.

Production Example 2

Under conditions described later, coated granular fertilizers wereproduced by coating granular urea (large granular urea, particle size:about 3 mm, number of granule per gram: 60) with urethane resins of rawmaterial composition (E) described in Table 2.

In a rotary vessel, 1000 parts by weight of granular urea was made intotumbling condition, and the granular urea was heated up to about 70° C.by hot air. Next, 20 parts by weight of an unhardened urethane resinhaving the composition (E) described in Table 2 was added and kept thetumbling condition under heating for 8 minutes or more. Further,addition of the unhardened urethane resin and keeping of the tumblingcondition under heating were repeated until the total amount of theunhardened urethane resin added reached 100 parts by weight. Thereafter,the mixture was cooled down to around room temperature, to obtain coatedgranular urea (E).

Test Example 2 (Test of Elution Property of Urea in Coated GranularFertilizer)

7.5 g of the coated granular fertilizer obtained in Production Examples1 and 2 was placed in a 100 ml glass tube, 100 ml of ion-exchanged waterwas added thereto and the mixture was allowed to stand still at 25° C.After given time, a small amount of the mixture was sampled, and theurea content eluted from the coated fertilizer was measured. The resultsare given in Table 4.

TABLE 4 Coated granular fertilizer Elution ratio after 35 days (%)Coated granular urea (A) 42 Coated granular urea (B) 40 Coated granularurea (D) 33 Coated granular urea (E) 17 Coated granular urea (F) 12Coated granular urea (a) 61 Coated granular urea (b) 44

Production Example 3

The same procedures as Production example 1, except that using urethaneresins of raw material compositions (G)-(K) described in Table 5, gavecoated granular ureas (G)-(K).

Production Example 4

The same procedures as Production example 1, except that using urethaneresins of raw material compositions (L), (M), (P) and (Q) described inTable 6, gave coated granular ureas (L), (M), (P) and (Q).

Further, the same procedures as Production example 1, except that 10parts by weight of an unhardened urethane resin of raw materialcompositions (N) and (O) described in Table 6 were added per oneprocedure and that the tumbling condition was kept under heating for 5minutes or more, gave coated granular ureas (N) and (O).

TABLE 5 Name of Compound G H I J K Diisocyanate MDI (NCO equivalent:125) 32.9 34.1 34.1 31.8 30.1 Polyol 1,4-Butanediol (OH 4.7 4.9 6.3 4.3equivalent: 45) 1,6-Hexanediol (OH 11.3 equivalent: 59)Polycaprolactonediol B (OH 43.9 22.7 23.8 40.2 equivalent: 416)Polycaprolactonetriol C (OH 54.6 38.1 equivalent: 668) Castor oil (OHequivalent: 18.5 38.3 25.4 351) Catalyst 2,4,6-Tris(dimethylaminomethyl)0.05 0.05 0.05 0.05 0.05 phenol Total Amount (wt %) 100.05 100.05 100.05100.05 100.05 Crosslinking density 0.03 0.06 0.03 0.04 0.04

TABLE 6 Name of Compound L M N O P Q Diisocyanate MDI (NCO 33.5 33.140.9 40.9 40.1 41.8 equivalent: 125) Polyol 1,4-Butanediol (OH 4.8 6.011.5 10.6 8.7 9.0 equivalent: 45) Polycaprolactonediol B 20.4 40.0 13.9(OH equivalent: 416) Polycaprolactonediol D 17.0 (OH equivalent: 265)Polycaprolactonediol E 16.5 (OH equivalent: 1002) PolycaprolactonetriolC 33.0 47.5 28.0 (OH equivalent: 668) Castor oil (OH 28.2 27.9 11.3 35.2equivalent: 351) Catalyst 2,4,6-Tris(dimethylaminomethyl) 0.05 0.05 0.010.01 phenol Total Amount (wt %) 100.05 100.05 100.00 100.00 100.01100.01 In Tables 5 and 6 described above, MDI (Sumidur 44S, manufacturedby Sumika Beyer Urethane K.K.), 1,4-butanediol (manufactured by WakoPure Chemical Industries, Ltd.), 1,6-hexanediol (manufactured by WakoPure Chemical Industries, Ltd.), polycaprolactonediol B (Placcel 208,manufactured by Daicel Chemical Industries, Ltd.), polycaprolactonetriolC (Placcel 320, manufactured by Daicel Chemical Industries, Ltd.),polycaprolactonediol D (Placcel 205, manufactured by Daicel ChemicalIndustries, Ltd.), polycaprolactonediol E (Placcel 220, manufactured byDaicel Chemical Industries, Ltd.), castor oil (Castor Oil No. 1 forindustrial use, manufactured by Hokoku corporation) and2,4,6-tris(dimethylaminomethyl)phenol (TAP, manufactured by Kayaku AkzoCorporation) were used.

Test Example 3 (Test of Elution Property of Urea in Coated GranularFertilizer)

The same procedures as Test example 2 for the coated granular ureas(G)-(I), (K)-(N) and (P)-(Q) were conducted to measure the elutionratio.

The results are given in Table 7.

TABLE 7 Coated granular fertilizer Elution ratio after 35 days (%)Coated granular urea (G) 35 Coated granular urea (H) Nearly 0 Coatedgranular urea (I) 18 Coated granular urea (K) 19 Coated granular urea(L) 3 Coated granular urea (M) 10 Coated granular urea (N) 14 Coatedgranular urea (P) 46 Coated granular urea (Q) 48

Reference Example 2 (Production of Urethane Resin Film)

A urethane resin film (L) or (M) was produced by the same procedures asReference Example 1.

Test Example 3 (Degradation of Urethane Resin Film in Soil)

The same tests were conducted as Test example 1 by using the urethaneresin film (L) and (M). The results are given in Table 8.

TABLE 8 Film Reduction in soil after 3 months (%) L 10.8 M 8.7

Production Example 6

Eight (8) parts by weight ofN-(1,1,3-trimethyl-2-oxa-4-indanyl)-5-chloro-1,3-dimethylpyrazole-4-carboxamide,1.6 parts by weight of hydrous silicon dioxide (TOKUSEAL GU-N,manufactured by Tokuyama Soda Co., Ltd.) and 8 parts by weight ofbentonite (BENTONITE FUJI, manufactured by Hojun Kogyo K.K.) were mixedsufficiently, then, pulverized by a jet mill. 17.6 parts by weight ofthe pulverized material obtained above, 3 parts by weight of polyvinylalcohol (mixture of 2.5 parts by weight of GOHSENOL GL-05 (manufacturedby Nippon Synthetic Chemical Industry Co., Ltd.) and 0.5 parts by weightof PVA 217S (manufactured by Kuraray Co., Ltd.)), 12 parts by weight ofbentonite (BENTONITE FUJI, manufactured by Hojun Kogyo K.K.), 2 parts byweight of polyoxyethylene styryl phenyl ether (SOLPOL T-20, manufacturedby Toho Chemical Industry Co., Ltd.) and 50.4 parts by weight of acalcium carbonate powder (TANCAL NN200, manufactured by Nitto FunkaKogyo K.K.) were mixed sufficiently in a juice mixer, to obtain a powdermixture. To the powder mixture was added 15 parts by weight of watercontaining 7.5 parts by weight of granulated sugar and 7.5 parts byweight of urea dissolved therein, and the mixture was kneadedsufficiently. The resultant kneaded material was granulated by a compactextrusion granulation machine equipped with a 0.9 mmφ screen, and theparticle size was regulated, then, the granules were dried at 60° C. for15 minutes to obtain an inner core in the form of cylinder (granulesize: 1400 to 850 μm, average diameter of cross-section: 0.9 mmφ).

In a rotary bath, 100 parts by weight of the above-mentioned inner corewas made into tumbling condition, and the inner core was heated up toabout 80° C. by hot air. Next, 0.25 parts by weight of an unhardenedurethane resin (F) described in Table 2 was added. The unhardenedurethane resin was prepared by mixing the polyol (F) (melted at 50° C.)described in Table 2 with 4,6-tris(dimethylaminomethyl)phenol(catalyst)in advance and adding an aromatic diisocyanate (melted at 50° C.) justbefore the use. After addition of the unhardened urethane resin, thetumbling condition was kept under heating for 3 minutes or more.Further, addition of the unhardened urethane resin and keeping of thetumbling condition under heating for 3 minutes were repeated until thetotal amount of the unhardened urethane resin added reached 3.00 partsby weight. Thereafter, the mixture was cooled down to around roomtemperature, to obtain coated pesticidal granule (F).

Production Example 7

Eight (8) parts by weight ofN-(1,1,3-trimethyl-2-oxa-4-indanyl)-5-chloro-1,3-dimethylpyrazole-4-carboxamide,1.6 parts by weight of hydrous silicon dioxide (TOKUSEAL GU-N,manufactured by Tokuyama Soda Co., Ltd.) and 8 parts by weight ofbentonite (BENTONITE FUJI, manufactured by Hojun Kogyo K.K.) were mixedsufficiently, then, pulverized by a jet mill. 17.6 parts by weight ofthe crushed material obtained above, 4.5 parts by weight of a pulverizedmixture of 3.15 parts by weight of[(E)-1-(2-chloro-1,3-thiazol-4-ylmethyl)-3-methyl-2-nitroquanidine] and1.35 parts by weight of clay (SHOKOSAN Clay S, manufactured by ShokosanKogyosho K.K.), 3 parts by weight of a mixture of 2.5 parts by weight ofpolyvinyl alcohol (GOHSENOL GL-05 (manufactured by Nippon SyntheticChemical Industry Co., Ltd.) and 0.5 parts by weight of PVA 217S(manufactured by Kuraray Co., Ltd.), 12 parts by weight of bentonite(BENTONITE FUJI, manufactured by Hojun Kogyo K.K.), 2 parts by weight ofpolyoxyethylene styryl phenyl ether (SOLPOL T-20, manufactured by TohoChemical Industry Co., Ltd.) and 51.9 parts by weight of a calciumcarbonate powder (TANCAL NN200, manufactured by Nitto Funka Kogyo K.K.)were mixed sufficiently in a juice mixer, to obtain a powder mixture. Tothe powder mixture was added 15 parts by weight of water containing 12.0parts by weight of granulated sugar and 1.5 parts by weight of ureadissolved therein, and the mixture was kneaded sufficiently. Theresultant kneaded material was granulated by a compact extrusiongranulation machine equipped with a 0.9 mmφ) screen, and the particlesize was regulated, then, the granules were dried at 60° C. for 15minutes to obtain an inner core in the form of cylinder (granule size:1400 to 850 μm, average diameter of cross-section: 0.9 mmφ).

In a rotary bath, 100 parts by weight of the above-mentioned inner corewas made into tumbling condition, and the inner core was heated up toabout 70° C. by hot air, 4 parts by weight of liquid paraffin was addedand kept the tumbling condition for 10 minutes. Next, 0.25 parts byweight of an unhardened urethane resin (E) described in Table 2 wasadded. The unhardened urethane resin (E) was prepared by mixing thepolyol (F) (melted at 50° C.) described in Table 2 with4,6-tris(dimethylaminomethyl)phenol(catalyst) in advance and adding anaromatic diisocyanate (melted at 50° C.) just before the use. Afteraddition of the unhardened urethane resin, the tumbling condition waskept under heating for 3 minutes or more. Further, addition of theunhardened urethane resin and keeping of the tumbling condition underheating for 3 minutes were repeated until the total amount of theunhardened urethane resin added reached 6.00 parts by weight.Thereafter, the mixture was cooled down to around room temperature, toobtain coated pesticidal granule (E).

Test Example 4

200 mg of the coated pesticidal granules (F) and (E) obtained above wasplaced in a 100 ml glass tube, 100 ml of ion-exchanged water was addedthereto and the mixture was allowed to stand still at 25° C. After giventime, a small amount of the mixture was sampled, and the contents ofN-(1,1,3-trimethyl-2-oxa-4-indanyl)-5-chloro-1,3-dimethylpyrazole-4-carboxamideand [(E)-1-(2-chloro-1,3-thiazol-4-ylmethyl)-3-methyl-2-nitroquanidine]eluted from the coated pesticidal granules was measured. The elutionratio ofN-(1,1,3-trimethyl-2-oxa-4-indanyl)-5-chloro-1,3-dimethylpyrazole-4-carboxamideafter one week was 32% for the coated pesticidal granule (F) and 24% forthe coated pesticidal granule (E). Further, the elution ratio of[(E)-1-(2-chloro-1,3-thiazol-4-ylmethyl)-3-methyl-2-nitroquanidine]after one week was 59% for the coated pesticidal granule (E).

Industrial Applicability

In the coated granule containing a bioactive substance, a resin forminga coat shows degradability in soil, and there is controllability ofsuitable elution of the bioactive substance.

The invention claimed is:
 1. A coated granule obtained by coating abioactive substance-containing granule with a urethane resin obtained byreaction of an aromatic diisocyanate with a polyol mixture consisting ofa polycaprolactonepolyol and a C2-C8 polymethylene glycol, and anopional additional triol, wherein the molar ratio of thepolycaprolactonepolyol to the polymethylene glycol is 1:20 to 20:1. 2.The coated granule according to claim 1, wherein the amount of thepolycaprolactonepolyol is 15 to 80 parts by weight based on 100 parts byweight of the total amount of the aromatic diisocyanate and the polyolmixture.
 3. The coated granule according to claim 1, wherein the amountof the polycaprolactonepolyol is 20 to 70 parts by weight based on 100parts by weight of the total amount of the aromatic diisocyanate and thepolyol mixture.
 4. The coated granule according to claim 1, wherein theamount of the polymethylene glycol is 1 to 25 parts by weight based on100 parts by weight of the total amount of the aromatic diisocyanate andthe polyol mixture.
 5. The coated granule according to claim 1, whereinthe polymethylene glycol is 1,4-butandiol or 1,6-hexanediol or a mixturethereof.
 6. The coated granule according to claim 1, wherein the amountof the aromatic diisocyanate is 10 to 49 parts by weight based on 100parts by weight of the total amount of the aromatic diisocyanate and thepolyol mixture.
 7. The coated granule according to claim 1, wherein thearomatic diisocyanate is 4,4′-diphenylmethanediisocyanate.
 8. The coatedgranule according to claim 1, wherein the polyol mixture consistspolycaprolactonepolyol, C2-C8 polymethylene glycol and at least oneselected from the group consisting of castor oil and hydrogenated castoroil.
 9. The coated granule according to claim 8, wherein the amounts ofthe polycaprolactonepolyol, C2-C8 polymethylene glycol, castor oiland/or hydrogenated castor oil and aromatic diisocyanate are 20 to 55parts, 1 to 15 parts, 10 to 40 parts and 10 to 49 parts by weight,respectively, based on 100 parts by weight of the total amount of thearomatic diisocyanate and the polyol mixture.
 10. The coated granuleaccording to claim 1, wherein the bioactive substance is a fertilizer.11. The coated granule according to claim 1, wherein the bioactivesubstance is a pesticide.
 12. The coated granule according to claim 1,wherein the polyol mixture includes the optional additional triol, andwherein the optional additional triol is selected from the groupconsisting of castor oil, hydrogenated castor oil, and mixtures thereof.13. A coated granule obtained by coating a bioactivesubstance-containing granule with a urethane resin obtained by reactionof an aromatic diisocyanate with a polyol mixture consisting of apolyesterpolyol and a C2-C8 polymethylene glycol selected from the groupconsisting of 1,4-butandiol, 1,6-hexanediol and mixtures thereof, and anoptional additional triol, wherein the molar ratio of thepolyesterpolyol to the polymethylene glycol is 1:20 to 20:1.
 14. Acoated granule obtained by coating a bioactive substance-containinggranule with a urethane resin obtained by reaction of an aromaticdiisocyanate with a polyol mixture consisting of a polyesterpolyol and aC2-C8 polymethylene glycol, and an additional triol, wherein the molarratio of the polyesterpolyol to the polymethylene glycol is 1:20 to20:1.
 15. The coated granule according to claim 14, wherein theadditional triol is selected from the group consisting of castor oil,hydrogenated castor oil, and mixtures thereof.
 16. A coated granuleobtained by coating a bioactive substance-containing granule with aurethane resin obtained by reaction of an aromatic diisocyanate with apolyol mixture consisting of a polyesterdiol, a C2-C8 polymethyleneglycol and a triol, wherein the molar ratio of the polyesterdiol to thepolymethylene glycol is 1:20 to 20:1.
 17. The coated granule accordingto claim 16, wherein the polyesterdiol has 15 wt% or more of anoxycarbonyl structure (-0-C(═O)—) part in the molecule.
 18. The coatedgranule according to claim 16, wherein the amount of the polyesterdiolis 15 to 80 parts by weight based on 100 parts by weight of the totalamount of the aromatic diisocyanate and the polyol mixture.
 19. Thecoated granule according to claim 16, wherein the amount of thepolymethylene glycol is 1 to 25 parts by weight based on 100 parts byweight of the total amount of the aromatic diisocyanate and the polyolmixture.
 20. The coated granule according to claim 16, wherein thepolymethylene glycol is 1,4-butandiol or 1,6-hexanediol or a mixturethereof.
 21. The coated granule according to claim 16, wherein theamount of the aromatic diisocyanate is 10 to 49 parts by weight based on100 parts by weight of the total amount of the aromatic diisocyanate andthe polyol mixture.
 22. The coated granule according to claim 16,wherein the aromatic diisocyanate is 4,4′-diphenylmethanediisocyanate.23. The coated granule according to claim 16, wherein the amounts of thepolyesterdiol, C2-C8 polymethylene glycol, triol and aromaticdiisocyanate are 20 to 55 parts, 1 to 15 parts, 10 to 40 parts and 10 to49 parts by weight, respectively, based on 100 parts by weight of thetotal amount of the aromatic diisocyanate and the polyol mixture. 24.The coated granule according to claim 16, wherein the bioactivesubstance is a fertilizer.
 25. The coated granule according to claim 16,wherein the bioactive substance is a pesticide.